Clock



Patented Nov. 17, 1942 UNITED STATES: PATENT OFFICE CLOCK Edward M. Dawn, Chicago, Ill.

Application August 29, 1941, Serial No. 408,827

5 Claims. (Cl. 58-26) This invention relates to a clock and more particularly an electric clock, provided with hour, minute and second shafts.

It is an object of this invention to provide a more effective means than heretofore employed Y diately observable indication of the stopping of the clock.

Other and further objects and advantages of the invention will be apparent from the following description when taken in connection with the accompanying drawing, wherein:

Fig. l is a face view of an electric clock embodying the invention;

Fig. 2 is a view in vertical section taken substantially along the line 2-2 of Fig. 4;

Fig. 3 is a View in vertical section taken substantially along the line 3-3 of Fig. 4;

Fig. 4 is a view in vertical section taken substantially along the line 4-4 of Fig. 3;

Fig. 5 is an exploded view in perspective of certain parts of the luminous indicator embodied in the invention;

Fig. 6 is a fragmentary View in horizontal section taken substantially along the line 5 of Fig. 3; and

Fig. '7 is a fragmentary view in oblique section taken along the line I-l of Fig. l.

As shown in the drawing, the clock embodying the invention comprises a case 2 which may be of any conventional structure, preferably formed in two sections 4 and 6, Fig. 4, secured detachably together in any desired manner as by a number of screws 8, Fig. 7. The section 4 of the clock has secured to its front face or edge a mounting ring I0 for the usual clock crystal I2.

A minute hand I4 is mounted on the usual minute shaft I8 for rotation therewith and the hour hand I6 is mounted on the usual sleeve 20, Fig. 6. These hands are positioned over the dial plate 22 mounted upon the dial mounting plate 24 secured to the usual frame 26 of the clock operating mechanism in the customary manner as by bolts, not shown, and spacing sleeves 28 spacing the dial mounting plate from the forward frame plate 30. The dial plate 22 is provided with the usual hour characters indicating the hours and the five-minute intervals, as shown in Fig. l, and the edge of the dial is provided with an annular series oi sixty small openings 32 serving in cooperation with the minute hand I4 to indicate the minutes and also serving, as

'Y wil later appear, to indicate the seconds. The

mounting plate 24 is provided with a similar annular series of sixty small openings 34, see Fig. 4J aligned with the openings 32 in the dial plate.

Between the dial plate 22 and the mounting plate 24 there are interposed color filters 36 and 38, see Figs. 2 and 4. The color filter 3G may be in the form of a ring 40, as shown in Fig. 2, having an annular series of a plurality of angularly spaced radial projections 42 extending inwardly and received in suitable notches in the color filter member 38 which may take the form of a ring 44 Within the ring 40. The filter members 36 and 38 may be of any suitable translucent material, the member 36 being one color, for example,

red, and the filter member 38 being another color, for example, green. The radial projections 42 are preferably twelve in number and each is disposed in alignment with an opening 32 in the dial plate that is aligned radially with one of the hour numerals. It will be evident that the color lter members 36 and 38 may be of other constructions, as, for example, a disc or single ring having differently colored parts in l; which the part of one color provides an annular series of equally spaced markings aligned with certain equally spaced openings 32 and 34 on the dial plate 22 and the mounting plate 24, while the other differently colored part comprises an arcuate strip or series of markings between each of the adjacent markings of the first part.

Within the usual frame 26 of the clock operating mechanism a synchronous electric motor 46 y may be mounted in the usual fashion and this Tc the forward face of the insulating block 5D secured a pair of radially projecting arms 60 and 52. preferably of sheet metal, or copper strips aiiixed to the block in spaced relation as by pins or screws 64 and 65 extending through the block a suicient distance to engage and make electrical contact with the set screws 56 and A small lamp bulb 68, preferably of the panel type extensively used for illuminating radio dials, -nounted on a clipl 'l0 which may be formed of sheet metal or copper strip and provides an inl al cylindrical portion 'I2 receiving and frictionally clamping the base of the lamp bulb 68 in electrical contact with the side terminal in the base. The clip 7S is also formed to provide an arm 74 having along its opposite edges chans'naped flange pieces 'i6 forming clips receiving and frictionally clamping the opposite end et Y s ol the arm SS. The arm 62 is bent at right angles to provide a resilient contact blade 'i8 shaped at its outer end to engage the end or bottoni terminal of the lamp bulb 68.

An opaque shield 80 of cylindrical form is provided with a resilient clip or piece 82 which serves to il ictionally engage the surface of the lamp receii "f cylinder 'I2 and detachably clamp the shieo e5 to the lamp carrying clip 10. The shield 8G is closed at its outer end 84 while the mountcip 8i: extends axially from the opposite open end of the shield. The shield 8U is provided with an opening 86 for permitting the passage of the light lays from the lamp bulb 68 to the shield and through the openings 34 and 32 in the plates and Z22 and through the color lters 3G and 38 interposed between these plates. The parts mounting the lamp on the insulating block 50 so diniensioned and the opening 8f3 is so positioned in the shield 8O that this opening is spaced irc-ni the concentric axis of the minute shaft i8, the hour` sleeve 2G and the seconds gear 48 so that it is successively aligned with each of the openthe similar openings 34.

the insulating block 58 is rotated by the seconds gear 48, the mounting arm 60 for the lamp bulb 63 is preferably provided with an inregi al extension for the arm 88 diametrically opposite to the arm 60 and carrying at its outer end a counterweight 90, the arm 88 and counterweight Si?) serving to counterbalance the weight of the arm Sil, lamp mounting clip l0, the lamp bulb E8 and the shield S, as well also as the arm G2 and its contact blade T8. By proper proportifning of the counterweight 9D the load imposed on the seconds gear 88 may be reduced to a minimum and may be not greater than the load imposed on such a gear by the usual seconds shaft and seconds hand.

Electrical connection to the slip rings 52 and 54 is established through a pair of brushes 92 and Oli having appropriately rounded heads and slidably mounted in an insulating block 9E iastened in a convenient manner as by suitable screws, not shown, to a bracket 98 fastened to the forward frame plate 30 of the clock operating mechanism. rThe brushes 92 and 94 are maintained in engagement with the slip rings 52 and 5f; by a pair of separate resilient electrically conducting straps ll and |02 engaging the outwardly projecting ends of said brushes and eX- lsnding along and affixed to one end of the block 9 Wires E54 and |06 connected to the straps IGS and H32 as by suitable terminal screws 68 connect the brushes to the low voltage secondary of a transformer l l!) mounted in any convenient ianner upon the frame 25, the primary of the transformer being connected to the supply cord in parallel to the motor 46.

The frame 25 which carries the clock operating mechanism is preferably fastened to the rear section 6 of the clock case as by means of brackets H2 of generally Z-shape fastened to the forward frame plate 38 and to the section 6.

It will be evident from the foregoing description that as the lamp bulb E8 rotates about the same axis with the minute hand I4 and the hour hand I8, the opening 88 in the shield 8i) is successively aligned with each pair of aligned openings s and 34 in the dial plate 22 on the mounting plate 24 and consequently a pencil of light rays is successively projected through the openings 32. In the preferred embodiment shown in the drawing a pencil of red rays will be projected "rem each opening 32, that is radially aligned with the hour numeral on the face oi' the dial and since in this preferred embodiment the member 38 is a green color lter, and portions of this filter are aligned with each set of four openings between the hour numerals, a green pencil of light will be projected for each second of each four-second interval between the fifth second interval. Thus, each ith second may be quickly distinguished from. the preceding and succeeding seconds which distinction is not readiy determined in the case of a clock having a rotating second hand. Also, by making the openings 32 sufficiently small the passage of each full second may be noted with great accuracy.

It will also be evident that by the structure disclosed, the applicant provides an inexpensive household clock of striking and pleasing appearance on which the passage oi the seconds may be observed under weak illumination of the clock or even in the dark Changes may be made in the form, construction and arrangement of the parts without departing from the spirit of the invention or sacriicing any of its attendant advantages, and the right is hereby reserved to make all such changes as fairly fall within the scope of the following claims.

I claim:

i. A clock having a dial plate with an annular series ci spaced light-transmitting portions, a clock train having a seconds gear, a lamp behind the dial plate, means mounting the lamp for movement by the gear along a circular path concentric to the axis of said annular series of light-transmitting portions of the dial plate, a shield between said lamp and said dial plate and having a light-transmitting portion spaced from said axis a distance egual to the radius of the annular series of light-transmitting portions of the dial plate whereby as the seconds gear rotates light rays are rojected successively through said light-transmitting portions of the dial plate.

2. A clock having a time indicating face plate having hour-signifying indicia, said face plate having an annular series of sixty spaced lighttransmitting portions. an hour hand cooperating with said indicia to indicate the hours, a minute hand cooperating with said light-transmitting portion to indicate the minutes, a clock train driving said hour and minute hands and including a seconds grear, a lamp positioned behind said dial plate, means mounting the lamp for movement by the seconds gear along a circular path concentric to the axis of f=aid annular series of light-transmitting portions of the dial plate, a shield between said lamp and plate and have ing the light-transmitting portions spaced from said axis a distance equal to the radius oi the annular` series of light-transmitting portions of the dial plate to project light rays successively through the light-transmitting portions of the dial plate, said projected rays being oi one color for each period of a predetermined number ci" seconds and oi a different color for each second in each suc-h period.

3. An electric clock comorising a dial plate having hour-signifying indicia` said dial plate having an annular series of sixty spaced openings, an hour hand cooperating with the hour indicia to indicate the hours. a minute hand cooperating with openings to indicate the minutes, an electrically driven clock train driving said hour and minute hands, said train including a seconds gear, a mounting plate for dial plate, said mounting plate having a second annular series oi sixty spaced openings aligned with the openings in the dial plate, a. lamp behind said mounting plate, means mounting said lamp for movement by the seconds gear along a circular path concentric to the common axis of said annular series of openings in the dial plate and the mounting plate, a shield on said lamp and having a light-transmitting portion spaced from said axis a distance equal to the radii of the annular series of openings in the dial and mounting plates to project light rays successively through the aligned openings in the dial and mounting plates, means providing a color lter of one color for each iifth pair or openF ings in the dial and mounting plates and a color filter of another color for each four pairs of aligned openings between each said fifth pair of aligned openings.

i. An electric clock comprising a time-indicating face plate, said face plate having an annular series of sixty spaced light-transmitting portions, a clock train having a seconds gear, a lamp behind said face plate, means mounting said lamp for movement by said seconds gear along a circular path concentric to the axis of said annular series of light-transmitting portions oi the face plate, a light-directing shield having a light-transmitting portion spaced from said axis a distance equal to the radius oi said annular series of light-transmitting portions of the face plate, said mounting means including an insulator secured to said seconds gear, a pair of slip rings mounted on said insulator, stationary brushes engaging said slip rings and oonnecting to a source of electricity and a pair of electrically conducting brackets secured to said insulator and connected to said slip rings, said brackets being respectively constructed and arranged to receive the lamp and establish electric connection 'thereto from the slip rings.

5. An electric clock comprising a time-indicating face plate, said face plate having an annular series of sixty spaced light-transmitting portions, a clock train having a seconds gear, a lamp behind said face plate, means mounting said lamp for movement by said seconds gear along a circular path concentric to the axis of said annular series of light-transmitting portions'oi the face plate, a light-directing shield having a light-transmitting portion spaced from said axis a distance equal to the radius of said annular series or light-transmitting portions of the face plate, said mounting means including an insulator secured to said seconds gear, a pair of slip rings mounted on said insulator, stationary brushes engaging said slip rings and connecting to a source of electricity and a pair of electrically conducting brackets secured to said insulator and connected to said slip rings, one oi said rackets having an arm projecting radiaily from the insulator, a metal collar receiving the lamp to establish electric contact with the side terminal oi the lamp base and having an integral clip for detachably receiving the free end of said arm, the other of said brackets having a radially projecting resilient arm engaging the end termina1 oi the base of the lamp to establish electric connection thereto.

EDWARD M. DAWN. 

